My new laptop...

I bought a new iBook G3 12" from ebay yesterday for ~$695.00 USD. It features firewire, two usb ports, 700MHz g3 processor, 256mb ram, combo dvd/cdrw, 16mb ati graphics, os x 10.3 jaguar, and is in good physical shape. I was wondering if anyone had some recommendations software wise for me. I'd like to get more of a feel for OS X by trying out native software for it. If you would like to recommend alternatives to GNU/Linux or compatible software titles which can be compiled easily on OS X using the GNU compiler suite, etc, please do. Thank's in advance.